Inspection of antimicrobial remains in bovine milk in Egypt and Saudi Arabia employing a bacteriological test kit and HPLC-MS/MS with estimation of risk to human health

Veterinary medicine uses antibiotics randomly for treatment and growth promotion. Milk of dairy animals contains substantial quantities of antibiotics that have harmful effects on health. It is therefore necessary to test commercially available milk using immunological, chromatographic, or microbiological methods to confirm the absence of antibiotic residues. This study aims to perform a microbiological test, followed by a quantitative confirmation analysis, on raw milk to assess the presence of antibiotic residues. Tests were conducted on 200 milk samples collected from markets and farms in Saudi Arabia and Egypt. The microbial inhibitor test (Delvotest SP-NT) revealed that 40 samples were positive for antibiotic residues. The positive samples were further tested using liquid chromatography-tandem mass spectrometry (LC-MS/MS) as a confirmatory quantitative test for 29 antibiotics that belong to five groups: tetracyclines, sulfonamides, fluoroquinolones, macrolides, and lactamases. Only four samples tested positive for oxytetracycline residues above the maximum residue limit. Based on these results, researchers suggest a monitoring system that considers both microbial and HPLC-MS/MS methods when detecting antibiotic residues in bovine milk. The analysis of risk to human health revealed that antibiotic residues at the detected levels do not pose any health risks to consumers.

Veterinary medicine uses antibiotics randomly for treatment and growth promotion. Milk 26 of dairy animals contains substantial quantities of antibiotics that have harmful effects on health.

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It is therefore necessary to test commercially available milk with immunological, 28 chromatographic, or microbiological methods to avoid antibiotic residues. This study aims to 29 perform a microbiological test, followed by a quantitative confirmation analysis, on raw milk to

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Antibiotics are a broad group of medicines that are utilized to destroy or prevent bacterial 48 microorganisms from developing. In the field of human medicine, they are used to treat a variety 49 of microbial infections. In the field of animal husbandry, they are widely used for infection 50 treatment, but they are also illegally used for prophylaxis and growth promotion, which can boost 51 a farm's financial return [1,2]. Utilizing these products may deliver residues into milk, triggering

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The current study aimed to perform prescreening of raw milk specimens to detect antibiotic 106 residues by microbiological inhibitor test kits followed by confirmatory quantitative analysis by 107 an HPLC/MS-MS technique. Furthermore, antibiotic residues in milk were correlated with risk 108 estimation for human health. In this study, the novelty is the application of a microbiological       The washing step was done with 6 mL of 5% methanol in water (v/v), the cartridges were then 204 dried for 10 min. Then, elution of the analytes was done using 6 mL methanol, followed by

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In this study, the detection of antibiotic residues in milk samples was performed using a 232 microbial inhibitor test and liquid chromatography-mass spectrometry. Results of Delvotest SP-

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NT revealed that 40 out of 200 tested samples showed no color change or partial color change, 234 suggesting a positive result constituting 20 % of the total samples as shown in (Fig 1). After that, 235 all of the 40 positive samples were tested using HPLC-MS/MS method as a confirmatory test. analysis is presented in (Fig 2).

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Examining milk samples for detection of antibiotic residues in levels more than was set by 269 community legislation needs low-cost testing methods. Due to their effectiveness, microbial  [35] in Mitidja, Aggad et al. [36] in the west of Algeria and Titouche et al. [37] in Tizi-Ouzu.

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Those detected a higher percentage of antibiotic residues in milk (57, 89, 29, and 46 %,  To determine the threat posed to consumers by milk containing antibiotic residues at levels 307 exceeding the MRL, health risk estimations were conducted for confirmed positive milk samples 308 collected from dairy farms. The mean oxytetracycline concentrations in the tested milk samples 309 were 120, 132, 141, and 150 μg/kg. HQ for detected oxytetracycline remains in milk samples from 310 dairy farms was computed to estimate any health threats to consumers (Table 2). HQ is defined as 311 the ratio of the possible exposure to a material and the concentration where no harmful impacts 312 are noted. If HQ is less than or equal to one, the risk to human health will be insignificant, while 313 if HQ is exceeding one, the consumer is subjected to the risk. As the HQ for the detected residues 314 of oxytetracycline in milk samples from farms was less than one, so it may be presumed that there 315 were insignificant adverse impacts on the consumer health accompanying the intake of the